Keys on paper circuits

2012/05/25 Roa Zubia, Guillermo - Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Elektronika
• Teknologia

A solution for economical electronics is the realization of paper-based circuits. But the introduction of keyboards in these circuits is a technological challenge. A team at Harvard University has found a way to make keys that mimics the technology of capacitive touch screens.

The researchers have not added keys, but some of the areas that are part of the circuit perform the function of keys. Once the finger is placed in one of these areas, it acts as a conductive bridge in this part of the circuit, the electrical current is modified and the circuit detects it. And it not only works with your fingers, but also with fine gloves. “We’ve used gloves for medical check-ups, above 0.1 millimeters,” says researcher Aaron Mazzeo. “These gloves are common in sterile environments and contaminated environments such as hospitals. Our keyboard has the ability to detect fingers despite the presence of these gloves.” In fact, the capacitive contact screens of smartphones can also be used with these gloves.

What was done at Harvard University is a numeric keypad. A thin sheet of aluminum has been coated with a layer of paper that has “engraved” the circuit using a laser. It has cost them a total of 50 dollars, but they say they have the possibility to reduce this cost, and in this way they can make diagnostic chips of a single use cheap, for example, for use in impoverished countries.